The present invention is related to chemical compounds that have immunoregulatory activity, pharmaceutical compositions containing such compounds and methods of treatment or prevention.
Immunoregulatory abnormalities have been shown to exist in a wide variety of autoimmune and chronic inflammatory diseases, including systemic lupus erythematosis, chronic rheumatoid arthritis, type I and II diabetes mellitus, inflammatory bowel disease, biliary cirrhosis, uveitis, multiple sclerosis and other disorders such as Crohn""s disease, ulcerative colitis, bullous pemphigoid, sarcoidosis, psoriasis, autoimmune myositis, Wegener""s granulomatosis, ichthyosis, Graves ophthalmopathy and asthma.
Although the underlying pathogenesis of each of these conditions may be quite different, they have in common the appearance of a variety of autoantibodies and self-reactive lymphocytes. Such self-reactivity may be due, in part, to a loss of the homeostatic controls under which the normal immune system operates. Similarly, following a bone-marrow or an organ transplantation, the host lymphocytes recognize the foreign tissue antigens and begin to produce both cellular and humoral responses including antibodies, cytokines and cytotoxic lymphocytes which lead to graft rejection.
One end result of an autoimmune or a rejection process is tissue destruction caused by inflammatory cells and the mediators they release. Anti-inflammatory agents such as NSAID""s act principally by blocking the effect or secretion of these mediators but do nothing to modify the immunologic basis of the disease. On the other hand, cytotoxic agents, such as cyclophosphamide, act in such a nonspecific fashion that both the normal and autoimmune responses are shut off. Indeed, patients treated with such nonspecific immunosuppressive agents are as likely to succumb to infection as they are to their autoimmune disease.
Cyclosporin A is a drug used to prevent rejection of transplanted organs. FK-506 is another drug approved for the prevention of transplant organ rejection, and in particular, liver transplantation. Cyclosporin A and FK-506 act by inhibiting the body""s immune system from mobilizing its vast arsenal of natural protecting agents to reject the transplant""s foreign protein. Cyclosporin A was approved for the treatment of severe psoriasis and has been approved by European regulatory agencies for the treatment of atopic dermatitis.
Though they are effective in delaying or suppressing transplant rejection, Cyclosporin A and FK-506 are known to cause several undesirable side effects including nephrotoxicity, neurotoxicity, and gastrointestinal discomfort. Therefore, an immunosuppressant without these side effects still remains to be developed and would be highly desirable.
While the main use for immunosuppressants is in treating bone marrow, organ and transplant rejection, other uses for such compounds include the treatment of arthritis, in particular, rheumatoid arthritis, insulin and non-insulin dependent diabetes, multiple sclerosis, psoriasis, inflammatory bowel disease, Crohn""s disease, lupus erythematosis and the like.
Thus, the present invention is focused on providing immunosuppressant compounds that are safer and more effective than prior compounds, having a better safety profile. These and other objects will be apparent to those of ordinary skill in the art from the description contained herein.
The present invention relates to a compound represented by formula 1: 
as well as the pharmaceutically acceptable salts and hydrates thereof, wherein:
X is O, S, NR1 or (CH2)1-2, optionally substituted with 1-4 halo groups;
R1 is H, C1-4 alkyl or haloC1-4 alkyl;
R1a is H, OH, C1-4 alkyl, or OC1-4 alkyl, the alkyl and alkyl portions being optionally substituted with 1-3 halo groups;
R1b represents H, OH, C1-4 alkyl or haloC1-4 alkyl;
each R2 is H, C1-4 alkyl or haloC1-4 alkyl; and
R3 is H, OH, halo, OC1-4 alkyl or O-haloC1-4 alkyl.
The invention also relates to compounds represented by formula A: 
or a pharmaceutically acceptable salt or hydrate thereof, wherein:
X is O, S, NR1 or (CH2)1-2, optionally substituted with 1-4 halo groups;
R1 is H, C1-4 alkyl or haloC1-4 alkyl;
R1a is H, OH, C1-4 alkyl, or OC1-4 alkyl, the alkyl and alkyl portions being optionally substituted with 1-3 halo groups;
R1b represents H, OH, C1-4 alkyl or haloC1-4 alkyl;
R2 is H, C1-4 alkyl or haloC1-4 alkyl,
R3 is H, OH, halo, C1-4alkyl, OC1-4alkyl, O-haloC1-4alkyl or hydroxyC1-4alkyl,
Y is selected from the group consisting of: xe2x80x94CH2xe2x80x94, xe2x80x94C(O)xe2x80x94, xe2x80x94CH(OH)xe2x80x94, xe2x80x94C(xe2x95x90NOH)xe2x80x94, O and S, and
R4 is selected from the group consisting of: C4-14alkyl and C4-14alkenyl.
Pharmaceutical compositions and methods of treatment are also included.
As used herein the following terms are defined as set forth below unless otherwise indicated.
Alkyl includes straight as well as branched alkyl groups containing the indicated number of carbon atoms.
Halo includes F, Cl, I and Br.
Haloalkyl represents a straight or branched alkyl group substituted with at least one halo group, and being optionally substituted with up to the maximum number of halo groups.
The present invention relates to a compound represented by formula 1: 
as well as the pharmaceutically acceptable salts and hydrates thereof, wherein:
X is O, S, NR1 or (CH2)1-2, optionally substituted with 1-4 halo groups;
R1 is H, C1-4 alkyl or haloC1-4 alkyl;
R1a is H, OH, C1-4 alkyl, or OC1-4 alkyl, the alkyl and alkyl portions being optionally substituted with 1-3 halo groups;
R1b represents H, OH, C1-4 alkyl or haloC1-4 alkyl;
each R2 is H, C1-4 alkyl or haloC1-4 alkyl; and
R3 is H, OH, halo, OC1-4 alkyl or O-haloC1-4 alkyl.
In one aspect of the invention that is of particular interest, a compound of formula 1 is provided wherein X is O or (CH2)1-2, optionally substituted with 1-4 halo groups. Within this subset, all other variables are as originally defined.
More particularly, an aspect of the invention that is of particular interest relates to compounds of formula 1 wherein X is O or CH2. Within this subset, all other variables are as originally defined.
Even more particularly, an aspect of the invention that is interest relates to compounds of formula 1 wherein X is O. Within this subset, all other variables are as originally defined.
In another aspect of the invention that is of particular interest, a compound of formula 1 is provided wherein R1a is H or OH. Within this subset, all other variables are as originally defined.
In another aspect of the invention that is of particular interest, a compound of formula 1 is provided wherein R1b represents H or OH. Within this subset, all other variables are as originally defined.
In another aspect of the invention that is of particular interest, a compound of formula 1 is provided wherein R3 is H, OH, halo, OC1-4 alkyl or O-haloC1-4 alkyl. Within this subset, all other variables are as originally defined.
In another aspect of the invention that is of particular interest, a compound of formula 1 is provided wherein R2 is H or C1-4 alkyl. Within this subset, all other variables are as originally defined.
A group of compounds that is of particular interest is described in connection with formula 1 wherein:
X is O or (CH2)1-2, optionally substituted with 1-4 halo groups;
R1a is H or OH;
R1b represents H or OH;
R2 is H, C1-4 alkyl or haloC1-4 alkyl, and
R3 is H, OH, halo, OC1-4 alkyl or O-haloC1-4 alkyl.
Preferred compounds of the present invention include the following:
The invention described herein includes pharmaceutically acceptable salts and hydrates. Pharmaceutically acceptable salts include both the metallic (inorganic) salts and organic salts; a list of which is given in Remington""s Pharmaceutical Sciences, 17th Edition, pg. 1418 (1985). It is well known to one skilled in the art that an appropriate salt form is chosen based on physical and chemical stability, flowability, hydroscopicity and solubility. As will be understood by those skilled in the art, pharmaceutically acceptable salts include, but are not limited to salts of inorganic acids such as hydrochloride, sulfate, phosphate, diphosphate, hydrobromide, and nitrate or salts of an organic acid such as malate, maleate, fumarate, tartrate, succinate, citrate, acetate, lactate, methanesulfonate, p-toluenesulfonate or pamoate, salicylate and stearate. Similarly pharmaceutically acceptable cations include, but are not limited to sodium, potassium, calcium, aluminum, lithium and ammonium (especially ammonium salts with secondary amines). Preferred salts of this invention for the reasons cited above include potassium, sodium, calcium and ammonium salts. Also included within the scope of this invention are crystal forms, hydrates and solvates of the compounds of Formula I.
The invention also includes the compounds falling within formula 1 in the form of one or more stereoisomers, in substantially pure form or in the form of a mixture of stereoisomers. All such isomers are encompassed within the present invention.
Immunoregulatory agents as used herein include compounds that act to suppress the immune system in instances where immunosuppression is in order, such as in bone marrow, organ or transplant rejection, autoimmune and chronic inflammatory diseases, including systemic lupus erythematosis, chronic rheumatoid arthritis, type I and II diabetes mellitus, inflammatory bowel disease, biliary cirrhosis, uveitis, multiple sclerosis and other disorders such as Crohn""s disease, ulcerative colitis, bullous pemphigoid, sarcoidosis, psoriasis, ichthyosis, Graves ophthalmopathy and asthma.
More particularly, the compounds of the present invention are useful to treat or prevent a disease or disorder selected from the group consisting of: transplantation of organs or tissue, graft-versus-host diseases brought about by transplantation, autoimmune syndromes including rheumatoid arthritis, systemic lupus erythematosus, Hashimoto""s thyroiditis, multiple sclerosis, myasthenia gravis, type I diabetes uveitis, juvenile-onset or recent-onset diabetes mellitus, posterior uveitis, allergic encephalomyelitis, glomerulonephritis, post-infectious autoimmune diseases including rheumatic fever and post-infectious glomerulonephritis, inflammatory and hyperproliferative skin diseases, psoriasis, atopic dermatitis, contact dermatitis, eczematous dermatoses, seborrheic dermatitis, Lichen planus, Pemphigus, bullous pemphigoid, Epidermolysis bullosa, urticaria, angioedemas, vasculitis, erythema, cutaneous eosinophilia, Lupus erythematosus, acne, Alopecia areata, keratoconjunctivitis, vernal conjunctivitis, uveitis associated with Behcet""s disease, keratitis, herpetic keratitis, conical cornea, dystrophia epithelialis corneae, corneal leukoma, ocular pemphigus, Mooren""s ulcer, Scleritis, Graves"" opthalmopathy, Vogt-Koyanagi-Harada syndrome, sarcoidosis, pollen allergies, reversible obstructive airway disease, bronchial asthma, allergic asthma, intrinsic asthma, extrinsic asthma, dust asthma, chronic or inveterate asthma, late asthma and airway hyper-responsiveness, bronchitis, gastric ulcers, vascular damage caused by ischemic diseases and thrombosis, ischemic bowel diseases, inflammatory bowel diseases, necrotizing enterocolitis, intestinal lesions associated with thermal bums, Coeliac diseases, proctitis, eosinophilic gastroenteritis, mastocytosis, Crohn""s disease, ulcerative colitis, migraine, rhinitis, eczema, interstitial nephritis, Good-pasture""s syndrome, hemolytic-uremic syndrome, diabetic nephropathy, multiple myositis, Guillain-Barre syndrome, Meniere""s disease, polyneuritis, multiple neuritis, mononeuritis, radiculopathy, hyperthyroidism, Basedow""s disease, pure red cell aplasia, aplastic anemia, hypoplastic anemia, idiopathic thrombocytopenic purpura, autoimmune hemolytic anemia, agranulocytosis, pernicious anemia, megaloblastic anemia, anerythroplasia, osteoporosis, sarcoidosis, fibroid lung, idiopathic interstitial pneumonia, dermatomyositis, leukoderma vulgaris, ichthyosis vulgaris, photoallergic sensitivity, cutaneous T cell lymphoma, arteriosclerosis, atherosclerosis, aortitis syndrome, polyarteritis nodosa, myocardosis, scleroderma, Wegener""s granuloma, Sjogren""s syndrome, adiposis, eosinophilic fascitis, lesions of gingiva, periodontium, alveolar bone, substantia ossea dentis, glomerulonephritis, male pattern alopecia or alopecia senilis by preventing epilation or providing hair germination and/or promoting hair generation and hair growth, muscular dystrophy; Pyoderma and Sezary""s syndrome, Addison""s disease, ischemia-reperfusion injury of organs which occurs upon preservation, transplantation or ischemic disease, endotoxin-shock, pseudomembranous colitis, colitis caused by drug or radiation, ischemic acute renal insufficiency, chronic renal insufficiency, toxinosis caused by lung-oxygen or drugs, lung cancer, pulmonary emphysema, cataracta, siderosis, retinitis, pigentosa, senile macular degeneration, vitreal scarring, corneal alkali burn, dermatitis erythema multiforme, linear IgA ballous dermatitis and cement dermatitis, gingivitis, periodontitis, sepsis, pancreatitis, diseases caused by environmental pollution, aging, carcinogenesis, metastasis of carcinoma and hypobaropathy, disease caused by histamine or leukotriene-C4 release, Behcet""s disease, autoimmune hepatitis, primary biliary cirrhosis, sclerosing cholangitis, partial liver resection, acute liver necrosis, necrosis caused by toxin, viral hepatitis, shock, or anoxia, B-virus hepatitis, non-A/non-B hepatitis, cirrhosis, alcoholic cirrhosis, hepatic failure, fulminant hepatic failure, late-onset hepatic failure, xe2x80x9cacute-on-chronicxe2x80x9d liver failure, augmentation of chemotherapeutic effect, cytomegalovirus infection, HCMV infection, AIDS, cancer, senile dementia, trauma, and chronic bacterial infection.
Also embodied within the present invention is a method of preventing or treating resistance to transplantation or transplantation rejection of organs or tissues in a mammalian patient in need thereof, which comprises administering a therapeutically effective amount of the compound of Formula 1.
A method of suppressing the immune system in a mammalian patient in need thereof, which comprises administering to the patient an immune system suppressing amount of the compound of Formula 1 is yet another embodiment.
Most particularly, the method described herein encompasses a method of treating or preventing bone marrow or organ transplant rejection which is comprised of admininstering to a mammalian patient in need of such treatment or prevention a compound of formula 1, or a pharmaceutically acceptable salt or hydrate thereof, in an amount that is effective for treating or preventing bone marrow or organ transplant rejection.
The present invention also includes a pharmaceutical formulation comprising a pharmaceutically acceptable carrier and the compound of Formula 1 or a pharmaceutically acceptable salt or hydrate thereof. A preferred embodiment of the formulation is one where a second immunosuppressive agent is also included. Examples of such second immunosuppressive agents are, but are not limited to azathioprine, brequinar sodium, deoxyspergualin, mizaribine, mycophenolic acid morpholino ester, cyclosporin, FK-506 and rapamycin.
Methods for preparing the compounds of this invention are illustrated in the following schemes and examples. Alternative routes will be easily discernible to practitioners in the field. 
In Reaction Scheme 1, the differentially protected amino malonate 1 is reacted with bromide 2 and sodium hydride in DMF as described by Kiuche et. al. [J. Medicinal Chemistry 43, 2946-2961 (2000) and references cited therein] to provide compound 3. The t-butyl ester of compound 3 can be removed with HCl in a solvent such as THF to give the corresponding carboxylic acid. The 15 acid is then reduced to the alcohol with diborane in THF (see March, J. xe2x80x9cAdvanced Organic Chemistryxe2x80x9d, 4th ed., John Wiley and Sons, New York pp. 1208, 1214-1215). The alcohol can be converted to its benzyl ether 4 by several commonly used methods. One method is to react the alcohol with benzyl bromide and sodium hydride in a solvent such as THF. The ethyl ester of compound 4 is hydrolyzed to acid 5 by reaction with sodium hydroxide in a solvent mixture of ethanol and water. Compound 5 is converted to dibenzyl phosphonate 6 by a Mitsunobu reaction. A mixture of compound 5, dibenzylphosphate, triphenylphosphine and diethylazodicarboxylate (DEAD) in THF leads to compound 6. (see March, J. xe2x80x9cAdvanced Organic Chemistryxe2x80x9d, 4th ed., John Wiley and Sons, New York pp. 395-396). Removal of the benzyl protecting groups by hydrogenolysis gives the phosphate ester 7. 
In Reaction Scheme 2, a method is provided for the synthesis of phosphonate analogs. The hydroxy group of compound 5 (Reaction Scheme 1) is converted to a leaving group. In his scheme, compound 5 is reacted with triflic anhydride and triethylamine in a solvent such as THF to give the triflate ester 8. Other leaving groups such as a methanesulfonate, or p-toluene sulfonate esters or a halide can also be prepared by commonly known methods. Triflate 8 is then reacted with diethylmethylphosphonate anion in THF to give the protected phosphonate derivative 9. In this reaction, diethylmethylphosphonate in THF at reduced temperature is deprotonated with a base such as sodium hydride or lithium diisopropylamine in a solvent such as THF and this mixture is then reacted with compound 8 to give compound 9. Deprotection of compound 9 to give phosphonate derivative 10 is completed in two steps. One first hydrolyzes the diethyl ester under acidic or basic conditions. In this scheme, compound 9 is stirred with HCl in a mixture of ethanol and water, heating if necessary. Alternatively, one can stir compound 9 with sodium hydroxide in the same solvent mixture. Finally, the benzyl groups are removed by hydrogenation as described in Reaction Scheme 1.
The present compounds, including salts and hydrates thereof, are useful in the treatment of autoimmune diseases, including the prevention of rejection of bone marrow transplant, foreign organ transplants and/or related afflictions, diseases and illnesses.
The compounds of this invention can be administered by any means that effects contact of the active ingredient compound with the site of action in the body of a warm-blooded animal. For example, administration, can be oral, topical, including transdernmal, ocular, buccal, intranasal, inhalation, intravaginal, rectal, intracistemal and parenteral. The term xe2x80x9cparenteralxe2x80x9d as used herein refers to modes of administration which include subcutaneous, intravenous, intramuscular, intraarticular injection or infusion, intrasternal and intraperitoneal.
The compounds can be administered by any conventional means available for use in conjunction with pharmaceuticals, either as individual therapeutic agents or in a combination of therapeutic agents. They can be administered alone, but are generally administered with a pharmaceutical carrier selected on the basis of the chosen route of administration and standard pharmaceutical practice.
The dosage administered will be dependent on the age, health and weight of the recipient, the extent of disease, kind of concurrent treatment, if any, frequency of treatment and the nature of the effect desired. Usually, a daily dosage of active ingredient compound will be from about 0.1-500 milligrams per day. Ordinarily, from 10 to 100 milligrams per day in one or more applications is effective to obtain desired results. These dosages are the effective amounts for the treatment of autoimmune diseases, the prevention of rejection of foreign organ transplants and/or related afflictions, diseases and illnesses.
The active ingredient can be administered orally in solid dosage forms, such as capsules, tablets, troches, dragees, granules and powders, or in liquid dosage forms, such as elixirs, syrups, emulsions, dispersions, and suspensions. The active ingredient can also be administered parenterally, in sterile liquid dosage forms, such as dispersions, suspensions or solutions. Other dosages forms that can also be used to administer the active ingredient as an ointment, cream, drops, transdermal patch or powder for topical administration, as an ophthalmic solution or suspension formation, i.e., eye drops, for ocular administration, as an aerosol spray or powder composition for inhalation or intranasal administration, or as a cream, ointment, spray or suppository for rectal or vaginal administration.
Gelatin capsules contain the active ingredient and powdered carriers, such as lactose, starch, cellulose derivatives, magnesium stearate, stearic acid, and the like. Similar diluents can be used to make compressed tablets. Both tablets and capsules can be manufactured as sustained release products to provide for continuous release of medication over a period of hours. Compressed tablets can be sugar coated or film coated to mask any unpleasant taste and protect the tablet from the atmosphere, or enteric coated for selective disintegration in the gastrointestinal tract.
Liquid dosage forms for oral administration can contain coloring and flavoring to increase patient acceptance.
In general, water, a suitable oil, saline, aqueous dextrose (glucose), and related sugar solutions and glycols such as propylene glycol or polyethylene gycols are suitable carriers for parenteral solutions. Solutions for parenteral administration preferably contain a water soluble salt of the active ingredient, suitable stabilizing agents, and if necessary, buffer substances. Antioxidizing agents such as sodium bisulfite, sodium sulfite, or ascorbic acid, either alone or combined, are suitable stabilizing agents. Also used are citric acid and its salts and sodium EDTA. In addition, parenteral solutions can contain preservatives, such as benzalkonium chloride, methyl- or propylparaben, and chlorobutanol.
Suitable pharmaceutical carriers are described in Remington""s Pharmaceutical Sciences, A. Osol, a standard reference text in this field.
For administration by inhalation, the compounds of the present invention may be conveniently delivered in the form of an aerosol spray presentation from pressurized packs or nebulisers. The compounds may also be delivered as powders which may be formulated and the powder composition may be inhaled with the aid of an insufflation powder inhaler device. The preferred delivery system for inhalation is a metered dose inhalation (MDI) aerosol, which may be formulated as a suspension or solution of a compound of Formula I in suitable propellants, such as fluorocarbons or hydrocarbons.
For ocular administration, an ophthalmic preparation may be formulated with an appropriate weight percent solution or suspension of the compounds of Formula I in an appropriate ophthalmic vehicle, such that the compound is maintained in contact with the ocular surface for a sufficient time period to allow the compound to penetrate the corneal and internal regions of the eye.
Useful pharmaceutical dosage-forms for administration of the compounds of this invention can be illustrated as follows:
A large number of unit capsules are prepared by filling standard two-piece hard gelatin capsules each with 100 milligrams of powdered active ingredient, 150 milligrams of lactose, 50 milligrams of cellulose, and 6 milligrams magnesium stearate.
A mixture of active ingredient in a digestible oil such as soybean oil, cottonseed oil or olive oil is prepared and injected by means of a positive displacement pump into gelatin to form soft gelatin capsules containing 100 milligrams of the active ingredient. The capsules are washed and dried.
A large number of tablets are prepared by conventional procedures so that the dosage unit is 100 milligrams of active ingredient, 0.2 milligrams of colloidal silicon dioxide, 5 milligrams of magnesium stearate, 275 milligrams of microcrystalline cellulose, 11 milligrams of starch and 98.8 milligrams of lactose. Appropriate coatings may be applied to increase palatability or delay absorption.
A parenteral composition suitable for administration by injection is prepared by stirring 1.5% by weight of active ingredient in 10% by volume propylene glycol. The solution is made to volume with water for injection and sterilized.
An aqueous suspension is prepared for oral administration so that each 5 milliliters contain 100 milligrams of finely divided active ingredient, 100 milligrams of sodium carboxymethyl cellulose, 5 milligrams of sodium benzoate, 1.0 grams of sorbitol solution, U.S.P., and 0.025 milliliters of vanillin.
The same dosage forms can generally be used when the compounds of this invention are administered stepwise or in conjunction with another therapeutic agent. When drugs are administered in physical combination, the dosage form and administration route should be selected depending on the compatibility of the combined drugs. Thus the term coadministration is understood to include the administration of the two agents concomitantly or sequentially, or alternatively as a fixed dose combination of the two active components.